共查询到20条相似文献,搜索用时 62 毫秒
1.
Increased erythritol production in fed-batch cultures of Torula sp. by controlling glucose concentration 总被引:2,自引:0,他引:2
D-K Oh C-H Cho J-K Lee S-Y Kim 《Journal of industrial microbiology & biotechnology》2001,26(4):248-252
The effect of glucose concentration on erythritol production by Torula sp. was investigated. The maximum volumetric productivity of erythritol was obtained at an initial glucose concentration
of 300 g l−1 in batch culture. The volumetric productivity was maximal at a controlled glucose concentration of 225 g l−1, reducing the lag time of the erythritol production. A fed-batch culture was established with an initial glucose concentration
of 300 g l−1 and with a controlled glucose concentration of 225 g l−1 in medium containing phytic acid as a phosphate source. In this fed-batch culture, a final erythritol production of 192 g
l−1 was obtained from 400 g l−1 glucose in 88 h. This corresponded to a volumetric productivity of 2.26 g l−1 h−1 and a 48% yield. Journal of Industrial Microbiology & Biotechnology (2001) 26, 248–252.
Received 26 September 2000/ Accepted in revised form 16 January 2001 相似文献
2.
Broth containing 152 g glycerol l−1 from Candida krusei culture was converted to 1,3-propanediol by Klebsiella pneumoniae. Residual glucose in the broth promoted growth of K. pneumoniae while acetate was inhibitory. After desalination treatment of glycerol broth by electrodialysis, the acetate in the broth was removed. A fed-batch culture with electrodialytically pretreated broth as␣substrate was developed giving 53 g 1,3- propanediol l−1 with a yield of 0.41 g g−1 glycerol and a productivity of 0.94 g l−1 h−1. 相似文献
3.
Kim JH Han KC Koh YH Ryu YW Seo JH 《Journal of industrial microbiology & biotechnology》2002,29(1):16-19
Xylitol, a functional sweetener, was produced from xylose by biological conversion using Candida tropicalis ATCC 13803. Based on a two-substrate fermentation using glucose for cell growth and xylose for xylitol production, fed-batch
fermentations were undertaken to increase the final xylitol concentration. The effects of xylose and xylitol on xylitol production
rate were studied to determine the optimum concentrations for fed-batch fermentation. Xylose concentration in the medium (100
g l−1) and less than 200 g l−1 total xylose plus xylitol concentration were determined as optimum for maximum xylitol production rate and xylitol yield.
Increasing the concentrations of xylose and xylitol decreased the rate and yield of xylitol production and the specific cell
growth rate, probably because of an increase in osmotic stress that would interfere with xylose transport, xylitol flux to
secretion to cell metabolism. The feeding rate of xylose solution during the fed-batch mode of operation was determined by
using the mass balance equations and kinetic parameters involved in the equations in order to increase final xylitol concentration
without affecting xylitol and productivity. The optimized fed-batch fermentation resulted in 187 g l−1 xylitol concentration, 0.75 g xylitol g xylose−1 xylitol yield and 3.9 g xylitol l−1 h−1 volumetric productivity. Journal of Industrial Microbiology & Biotechnology (2002) 29, 16–19 doi:10.1038/sj.jim.7000257
Received 15 October 2001/ Accepted in revised form 30 March 2002 相似文献
4.
Effects of methanol on expression of an anticoagulant hirudin in recombinant Hansenula polymorpha 总被引:1,自引:0,他引:1
A series of batch, fed-batch, and continuous cultures was carried out to analyze the effects of methanol on the fermentation
characteristics of recombinant Hansenula polymorpha for the production of hirudin, an anticoagulant. Hirudin expression efficiencies were greatly influenced by the methanol
concentrations in continuous and fed-batch culture modes. At a steady state of continuous culture, an optimum methanol concentration
of 1.7 g l−1 was determined at a dilution rate of 0.18 h−1 with 1.8 mg l−1 h−1 hirudin productivity. Journal of Industrial Microbiology & Biotechnology (2001) 27, 58–61.
Received 21 September 2000/ Accepted in revised form 10 June 2001 相似文献
5.
Jeffke T Jende D Mätje C Ehlers RU Berthe-Corti L 《Applied microbiology and biotechnology》2000,54(3):326-330
Photorhabdus luminescens, a bacterial symbiont of entomopathogenic biocontrol nematodes, was grown in batch and glucose fed-batch culture. The cell
density, bioluminescence, production of antibiotic substances, number of cells with inclusion bodies, glucose concentration
and oxygen uptake rate were recorded. The addition of 12.4 g l−1 glucose prolonged the growth, and the yield almost doubled, from 6.85 g l−1 to 12.45 g l−1 dry mass. The production of antibiotic substances increased by 140%. Bioluminescence was higher in the batch culture. A shift
of P. luminescens to phase II variants was not detected.
Received: 21 January 2000 / Received revision: 3 April 2000 / Accepted: 7 April 2000 相似文献
6.
Kim YS Lee JH Kim NH Yeom SJ Kim SW Oh DK 《Applied microbiology and biotechnology》2011,90(2):489-497
In the fed-batch culture of glycerol using a metabolically engineered strain of Escherichia coli, supplementation with glucose as an auxiliary carbon source increased lycopene production due to a significant increase in
cell mass, despite a reduction in specific lycopene content. l-Arabinose supplementation increased lycopene production due to increases in cell mass and specific lycopene content. Supplementation
with both glucose and l-arabinose increased lycopene production significantly due to the synergistic effect of the two sugars. Cell growth by the
consumption of carbon sources was related to endogenous metabolism in the host E. coli. Supplementation with l-arabinose stimulated only the mevalonate pathway for lycopene biosynthesis and supplementation with both glucose and l-arabinose stimulated synergistically only the mevalonate pathway. In the fed-batch culture of glycerol with 10 g l−1 glucose and 7.5 g l−1
l-arabinose, the cell mass, lycopene concentration, specific lycopene content, and lycopene productivity after 34 h were 42 g l−1, 1,350 mg l−1, 32 mg g cells−1, and 40 mg l−1 h−1, respectively. These values were 3.9-, 7.1-, 1.9-, and 11.7-fold higher than those without the auxiliary carbon sources,
respectively. This is the highest reported concentration and productivity of lycopene. 相似文献
7.
Corynebacterium acetoacidophilum RYU3161 was cultivated in al-histidine-limited fed-batch culture. To investigate the effect of cell growth on thel-proline production, 5l fed-batch culture was performed using an exponential feeding rate to obtain the specific growth rates (μ) of 0.04, 0.06,
0.08, and 0.1 h−1. The results show that the highest production ofl-proline was obtained at μ=0.04 h−1. The specificl-proline production rate (Qp) increased proportionally as a function of the specific growth rate, but decreased after it revealed the maximum value at
μ=0.08 h−1. Thus, the highest productivity ofl-proline was 1.66 g L−1 h−1 at μ=0.08 h−1. The results show that the production of L-proline inC. acetoacidophilum RYU3161 has mixed growth-associated characteristics. 相似文献
8.
Xin Zhao Cuimin Hu Siguo Wu Hongwei Shen Zongbao K. Zhao 《Journal of industrial microbiology & biotechnology》2011,38(5):627-632
Microbial lipid is a potential alternative feedstock for the biodiesel industry. New culture strategies remain to be developed
to improve the economics of microbial lipid technology. This work describes lipid production by the oleaginous yeast Rhodosporidium toruloides Y4 using a 15-l bioreactor with different substrate feeding strategies. Among these strategies, the intermittent feeding
mode gave a lipid productivity of 0.36 g l−1 h−1, whereas the constant glucose concentration II (CC-II) mode gave the highest lipid productivity of 0.57 g l−1 h−1. The repeated fed-batch mode according to the CC-II mode was performed with a duration time of 358 h, and the overall lipid
productivity was 0.55 g l−1 h−1. Our results suggested that substrate feeding modes had a great impact on lipid productivity and that the repeated fed-batch
process was the most appealing method by which to enhance microbial lipid production. 相似文献
9.
Over-production of human soluble B lymphocyte stimulator (hsBLyS) was carried out with four different fed-batch culture strategies
using lactose as inducer, instead of IPTG, in a fed-batch culture of Escherichia coli. As lactose acted as both inducer and carbon source, the best and simplest culture strategy was direct feeding of lactose
after batch culture, thereby giving hsBLyS at 3.7 g l−1 and a productivity of 0.11 g l−1 h−1.
Revisions requested 1 September 2005 and 11 November 2005; Revisions received 7 November 2005 and 4 January 2006 相似文献
10.
Industrial waste corn cob residue (from xylose manufacturing) without pretreatment was hydrolyzed by cellulase and cellobiase. The cellulosic hydrolysate contained 52.4 g l−1 of glucose and was used as carbon source for lactic acid fermentation by cells of Lactobacillus delbrueckii ZU-S2 immobilized in calcium alginate gel beads. The final concentration of lactic acid and the yield of lactic acid from glucose were 48.7 g l−1 and 95.2%, respectively, which were comparative to the results of pure glucose fermentation. The immobilized cells were quite stable and reusable, and the average yield of lactic acid from glucose in the hydrolysate was 95.0% in 12 repeated batches of fermentation. The suitable dilution rate of continuous fermentation process was 0.13 h−1, and the yield of lactic acid from glucose and the productivity were 92.4% and 5.746 g l−1 h−1, respectively. The production of lactic acid by simultaneous saccharification and fermentation (SSF) process was carried out in a coupling bioreactor, the final concentration of lactic acid was 55.6 g l−1, the conversion efficiency of lactic acid from cellulose was 91.3% and the productivity was 0.927 g l−1 h−1. By using fed-batch technique in the SSF process, the final concentration of lactic acid and the productivity increased to 107.6 g l−1 and 1.345 g l−1 h−1, respectively, while the dosage of cellulase per gram substrate decreased greatly. This research work should advance the bioconversion of renewable cellulosic resources and reduce environmental pollution. 相似文献
11.
Sirisansaneeyakul S Luangpipat T Vanichsriratana W Srinophakun T Chen HH Chisti Y 《Journal of industrial microbiology & biotechnology》2007,34(5):381-391
Production of lactic acid from glucose by immobilized cells of Lactococcus lactis IO-1 was investigated using cells that had been immobilized by either entrapment in beads of alginate or encapsulation in
microcapsules of alginate membrane. The fermentation process was optimized in shake flasks using the Taguchi method and then
further assessed in a production bioreactor. The bioreactor consisted of a packed bed of immobilized cells and its operation
involved recycling of the broth through the bed. Both batch and continuous modes of operation of the reactor were investigated.
Microencapsulation proved to be the better method of immobilization. For microencapsulated cells at immobilized cell concentration
of 5.3 g l−1, the optimal production medium had the following initial concentrations of nutrients (g l−1): glucose 45, yeast extract 10, beef extract 10, peptone 7.5 and calcium chloride 10 at an initial pH of 6.85. Under these
conditions, at 37 °C, the volumetric productivity of lactic acid in shake flasks was 1.8 g l−1 h−1. Use of a packed bed of encapsulated cells with recycle of the broth through the bed, increased the volumetric productivity
to 4.5 g l−1 h−1. The packed bed could be used in repeated batch runs to produce lactic acid. 相似文献
12.
The effects of silicate and glucose on growth and eicosapentaenoic acid (EPA) production by the diatom Nitzschia laevis were studied. By alternately altering the concentrations of silicate (2.7–64 mg l−1) and glucose (1–40 g l−1) in the medium, the highest cell dry weight (ca. 5.5 g l−1) was obtained at 20 g l−1 glucose and 32 mg l−1 silicate, while the highest specific growth rate (ca. 0.65 day−1) was obtained at a relatively low glucose concentration (5 g l−1) and high silicate concentrations (32–64 mg l−1). At glucose levels of 5 and 20 g l−1, EPA content was higher with lower silicate concentrations (2.7 and 16 mg l−1 silicate, respectively), while at a silicate level of 16 mg l−1, higher glucose concentrations (20–40 g l−1) facilitated EPA formation. The highest EPA yield (131 mg l−1) was obtained at 20 g l−1 glucose and 32 mg l−1 silicate, while the highest EPA productivity (15.1 mg l−1 day−1) was obtained at 20 g l−1 glucose and 64 mg l−1 silicate. Journal of Industrial Microbiology & Biotechnology (2000) 25, 218–224.
Received 08 May 2000/ Accepted in revised form 21 July 2000 相似文献
13.
Klebsiella oxytoca M5al is an excellent 1,3-propanediol (1,3-PD) producer, but too much lactic acid yielded greatly lessened the fermentation
efficiency for 1,3-PD. To counteract the disadvantage, four lactate deficient mutants were obtained by knocking out the ldhA gene of lactate dehydrogenase (LDH) of K. oxytoca M5al. The LDH activities of the four mutants were from 3.85 to 6.92% of the parental strain. The fed-batch fermentation of
1,3-PD by mutant LDH3, whose LDH activity is the lowest, was studied. The results showed that higher 1,3-PD concentration,
productivity, and molar conversion rate from glycerol to 1,3-PD can be gained than those of the wild type strain and no lactic
acid is produced under both anaerobic and microaerobic conditions. Sucrose fed during the fermentation increased the conversion
and sucrose added at the beginning increased the productivity. In fed-batch fermentation with sucrose as cosubstrate under
microaerobic conditions, the 1,3-PD concentration, conversion, and productivity were improved significantly to 83.56 g l−1, 0.62 mol mol−1, and 1.61 g l−1 h−1, respectively. Furthermore, 60.11 g l−1 2,3-butanediol was also formed as major byproduct in the broth. 相似文献
14.
Automated feeding strategies for high-cell-density fed-batch cultivation of Pseudomonas putida KT2440 总被引:1,自引:0,他引:1
Four automatic substrate feeding strategies were developed and investigated in this study to obtain rapid, repeatable, and reliable high cell densities of Pseudomonas putida KT2440 from glucose. Growth yield data of the key nutrients, Y
X/Glucose, Y
X/NH4, Y
X/PO4, Y
X/Mg, and Y
CO2/Glucose, were determined to be 0.41, 5.44, 13.70, 236, and 0.65 g g−1, respectively. Although standard exponential feeding strategy worked well when the predetermined μ was set at 0.25 h−1, an exponential glucose feeding strategy with online μ
max estimation resulted in a higher average biomass productivity (3.4 vs 2.8 g l−1 h−1). A CO2 production rate based pulse glucose feeding strategy also resulted in good overall productivity (3.0 g l−1 h−1) and can be used as an alternative to pH-stat or DO-stat feeding. A cumulative CO2 production based continuous feed with real-time cumulative glucose consumption estimation resulted in much higher biomass productivity (4.3 g l−1 h−1) and appears to be an excellent and reliable approach to fully automating high-cell-density fed-batch cultivation of P. putida. 相似文献
15.
Kim HS Jeon JW Kim BH Ahn CY Oh HM Yoon BD 《Applied microbiology and biotechnology》2006,70(4):391-396
Candida sp. strain SY16 produces a glycolipid-type biosurfactant, mannosylerythritol lipid (MEL-SY16), which can reduce the surface
tension of a culture broth from 72 to 30 dyne cm−1 and highly emulsify hydrocarbons when cultured in soybean-oil-containing media. As such, laboratory-scale fermentation for
MEL-SY16 production was performed using optimized conditions. In batch fermentation, MEL-SY16 was mainly produced during the
stationary phase of growth, and the concentration of MEL-SY16 reached 37 g l−1 after 200 h. The effect of pH control on the production of MEL-SY16 was also examined in batch fermentation. The highest
production yield of MEL-SY16 was when the pH was controlled at 4.0, and the production was significantly improved compared
to batch fermentation without pH control. In fed-batch fermentation, glucose and soybean oil (1:1, w/w) were used in combination
as the initial carbon sources for cell growth, and soybean oil was used as the feeding carbon source during the MEL production
phase. The feeding of soybean oil resulted in the disappearance of any foam and a sharp increase in the MEL production until
200 h, at which point the concentration of MEL-SY16 was 95 g l−1. Among the investigated culture systems, the highest MEL-SY16 production and volumetric production rate were achieved with
fed-batch fermentation. 相似文献
16.
This is an overview of the mutant strain Clostridium beijerinckii BA101 which produces solvents (acetone–butanol–ethanol, ABE) at elevated levels. This organism expresses high levels of amylases
when grown on starch. C. beijerinckii BA101 hydrolyzes starch effectively and produces solvent in the concentration range of 27–29 g l−1. C. beijerinckii BA101 has been characterized for both substrate and butanol inhibition. Supplementing the fermentation medium (MP2) with
sodium acetate enhances solvent production to 33 g l−1. The results of studies utilizing commercial fermentation medium and pilot plant-scale reactors are consistent with the results
using small-scale reactors. Pervaporation, a technique to recover solvents, has been applied to fed-batch reactors containing
C. beijerinckii BA101, and solvent production as high as 165 g l−1 has been achieved. Immobilization of C. beijerinckii BA101 by adsorption and use in a continuous reactor resulted in reactor productivity of 15.8 g l−1 h−1. Recent economic studies employing C. beijerinckii BA101 suggested that butanol can be produced at US$0.20–0.25 lb−1 by employing batch fermentation and distillative recovery. Application of new technologies such as pervaporation, fed-batch
culture, and immobilized cell reactors is expected to further reduce these prices.
Journal of Industrial Microbiology & Biotechnology (2001) 27, 287–291.
Received 12 September 2000/ Accepted in revised form 27 January 2001 相似文献
17.
Acetone butanol ethanol (ABE) was produced in an integrated fed-batch fermentation-gas stripping product-recovery system using Clostridium beijerinckii BA101, with H2 and CO2 as the carrier gases. This technique was applied in order to eliminate the substrate and product inhibition that normally restricts ABE production and sugar utilization to less than 20 g l–1 and 60 g l–1, respectively. In the integrated fed-batch fermentation and product recovery system, solvent productivities were improved to 400% of the control batch fermentation productivities. In a control batch reactor, the culture used 45.4 g glucose l–1 and produced 17.6 g total solvents l–1 (yield 0.39 g g–1, productivity 0.29 g l–1 h–1). Using the integrated fermentation-gas stripping product-recovery system with CO2 and H2 as carrier gases, we carried out fed-batch fermentation experiments and measured various characteristics of the fermentation, including ABE production, selectivity, yield and productivity. The fed-batch reactor was operated for 201 h. At the end of the fermentation, an unusually high concentration of total acids (8.5 g l–1) was observed. A total of 500 g glucose was used to produce 232.8 g solvents (77.7 g acetone, 151.7 g butanol, 3.4 g ethanol) in 1 l culture broth. The average solvent yield and productivity were 0.47 g g–1 and 1.16 g l–1 h–1, respectively. 相似文献
18.
Poly-(3-hydroxybutyrate) production from whey by high-density cultivation of recombinant Escherichia coli 总被引:2,自引:0,他引:2
Recombinant Escherichia coli strain GCSC 6576, harboring a high-copy-number plasmid containing the Ralstonia eutropha genes for polyhydroxyalkanoate (PHA) synthesis and the E. coli ftsZ gene, was employed to produce poly-(3-hydroxybutyrate) (PHB) from whey. pH-stat fed-batch fermentation, using whey powder
as the nutrient feed, produced cellular dry weight and PHB concentrations of 109 g l−1 and 50 g l−1 respectively in 47 h. When concentrated whey solution containing 210 g l−1 lactose was used as the nutrient feed, cellular dry weight and PHB concentrations of 87 g l−1 and 69 g l−1 respectively could be obtained in 49 h by pH-stat fed-batch culture. The PHB content was as high as 80% of the cellular dry
weight. These results suggest that cost-effective production of PHB is possible by fed-batch culture of recombinant E. coli using concentrated whey solution as a substrate.
Received: 19 December 1997 / Received revision: 17 March 1998 / Accepted: 20 March 1998 相似文献
19.
Lakkana Laopaiboon Pornthap Thanonkeo Prasit Jaisil Pattana Laopaiboon 《World journal of microbiology & biotechnology》2007,23(10):1497-1501
Sweet sorghum juice supplemented with 0.5% ammonium sulphate was used as a substrate for ethanol production by Saccharomyces cerevisiae TISTR 5048. In batch fermentation, kinetic parameters for ethanol production depended on initial cell and sugar concentrations.
The optimum initial cell and sugar concentrations in the batch fermentation were 1 × 108 cells ml−1 and 24 °Bx respectively. At these conditions, ethanol concentration produced (P), yield (Y
ps) and productivity (Q
p
) were 100 g l−1, 0.42 g g−1 and 1.67 g l−1 h−1 respectively. In fed-batch fermentation, the optimum substrate feeding strategy for ethanol production at the initial sugar
concentration of 24 °Bx was one-time substrate feeding, where P, Y
ps and Q
p
were 120 g l−1, 0.48 g g−1 and 1.11 g l−1 h−1 respectively. These findings suggest that fed-batch fermentation improves the efficiency of ethanol production in terms of
ethanol concentration and product yield. 相似文献
20.
Tiejun Liu Shigenobu Miura Tomohiro Arimura Min-Yi Tei Enoch Y. Park Mitsuyasu Okabe 《Biotechnology and Bioprocess Engineering》2005,10(6):522-527
Various processes which producel-lactic acid using ammonia-tolerant mutant strain,Rhizopus sp. MK-96-1196, in a 3 L airlift bioreactor were evaluated. When the fed-batch culture was carried out by keeping the glucose
concentration at 30 g/l, more than 140 g/l ofl-lactic acid was produced with a product yield of 83%. In the case of the batch culture with 200 g/l of initial glucose concentration, 121 g/L ofl-lactic acid was obtained but the low product yield based on the amount of glucose consumed. In the case of a continuous culture,
1.5 g/l/h of the volumetric productivity with a product yield of 71% was achieved at dilution rate of 0.024 h−1. Basis on these results three processes were evaluated by simple variable cost estimation including carbon source, steam,
and waste treatment costs. The total variable costs of the fed-batch and continuous cultures were 88% and 140%, respectively,
compared to that of batch culture. The fed-batch culture with highl-lactic acid concentration and high product yield decreased variable costs, and was the best-suited for the industrial production
ofl-lactic acid. 相似文献